Exchanges Catch Heat on Hill Over High-Speed Trading

By

Jenny Strasburg And

Scott Patterson

Updated Sept. 21, 2012 9:32 a.m. ET

WASHINGTON—Lawmakers, traders and market experts called for tighter controls of stock exchanges and high-speed trading firms Thursday, with some saying their pursuit of profits is complicating markets that already baffle most investors and have proved vulnerable to blowups.

Sens. Jack Reed (D., R.I.) and Mike Crapo (R., Idaho) and several witnesses at the Senate Banking subcommittee hearing took aim at the complex technological...